More slight improvements after review

Author: trinistr

library/tempfile/create_spec.rb

@@ -9,7 +9,7 @@
     end
   end
 
-  it "returns a new, open File instance placed in tmpdir" do
+  it "returns a new, open regular File instance placed in tmpdir" do
     @tempfile = Tempfile.create
     # Unlike Tempfile.open this returns a true File,
     # but `.should be_an_instance_of(File)` would be true either way.
@@ -109,7 +109,6 @@
       -> { Tempfile.create(:create_spec) }.should raise_error(ArgumentError, "unexpected prefix: :create_spec")
       -> { Tempfile.create([:create_spec]) }.should raise_error(ArgumentError, "unexpected prefix: :create_spec")
       -> { Tempfile.create(["create_spec", :temp]) }.should raise_error(ArgumentError, "unexpected suffix: :temp")
-
     end
   end
 
@@ -125,9 +124,11 @@
   end
 
   context "when called with a mode option" do
-    it "ORs it with the default mode, forcing it to be writable" do
+    it "ORs it with the default mode, forcing it to be readable and writable" do
       @tempfile = Tempfile.create(mode: File::RDONLY)
-      File.writable?(@tempfile.path).should be_true
+      @tempfile.puts "test"
+      @tempfile.rewind
+      @tempfile.read.should == "test\n"
     end
 
     it "raises NoMethodError if passed a String mode" do